Long-Term Phentermine Use Safe, Effective for Weight Loss
No difference in cardiovascular disease, death seen between those taking the drug for >12 versus ≤3 months
FRIDAY, March 29, 2019 (Pharmacist's Briefing) -- Patients taking phentermine for weight loss for more than three months experience greater weight loss without an increased risk for incident cardiovascular disease or death, according to a study published online March 21 in Obesity.
Kristina H. Lewis, M.D., from the Wake Forest School of Medicine in Winston-Salem, North Carolina, and colleagues used electronic health record data to identify 13,972 adults (84 percent female and 45 percent white) with a first phentermine prescription between 2010 and 2015. Patients were categorized by duration of use.
Patients had a mean baseline age of 43.5 years and a mean body mass index of 37.8 kg/m². The researchers found that at 24 months, longer-term users of phentermine had more weight loss, with patients using continuously for >12 months losing 7.4 percent more than those who used for no more than three months. There were 41 events of the composite outcome of cardiovascular disease or death (0.3 percent), with no significant difference between the groups.
"For patients who respond to and tolerate it, phentermine may be a safe and affordable way to achieve greater and longer-lasting weight loss, but we need clinical trials to provide more certainty," Lewis said in a statement. "At the moment, there is no change to the U.S. Food and Drug Administration labeling so doctors should use caution with the decision about prescribing it longer term."